This two part study will identify cell surface components involved in morphogenesis and malignancy. Part one is based on preliminary results that indicate that specific lectins bind to specific cell types in vivo, in the sea urchin embryo, and perturb specific cellular interactions mediated by these cell types. Lens culinaris hemagglutinin (LcH) binds to secondary mesenchyme cells, but not primary mesenchyme cells, and causes exogastrulation. Wheat germ agglutinin (WGA) binds to primary mesenchyme cells, but not secondary mesenchyme cells, and causes defective spine development. The spines were normal in LcH treated embryos and the gut attachments were normal in the WGA treated embryos. Specific sarccharides inhibited specific lectin binding to these specific cell types. Part one of the proposed study will: (1) binding to these specific cell types. Part one of the proposed study will: (1) binding to these specific cell types. Part one of the proposed study will: (1) evaluate several additional lectins for their in vivo binding to specific cell types and their effects on specific cellular interactions; (2) test free glycans for similar developmental effects; (3) isolate and purify the putative endogenous sea urchin lectins and glycans that mediate the cellular interactions under study, such as those responsible for gut attachment to the blastocoel roof, inhibited by LcH. Part two of this proposed study is based on preliminary results that led to the development of an assay to identify new cell surface markers, using over 100 different development of an assay to identify new cell surface markers, using over 100 different derivatized agarose beads. This assay will be utilized in the proposed study to identify specific cell surface markers that will be matched with known behavioral properties of normal and colon cancer human cell lines. Part one will provide the data for a competitive R01 proposal on characterization and molecular cloning of functional sea urchin lectins and characterization of the endogenous sea urchin of functional sea urchin lectins and characterization of the endogenous sea urchin lectin binding glycans. Part two will provide the data needed for a competitive R01 proposal on new cancer screening methods and drug development strategies based on the binding properties of cancer cells identified through the derivatized bean studies.